[Form 4] WESTLAKE CHEMICAL PARTNERS LP Insider Trading Activity

Rhea-AI Filing Summary

Jean-Marc Gilson, President and CEO and a director of Westlake Chemical Partners LP (WLKP), reported an open-market purchase of 11,803.485 common units on 08/27/2025 at a price of $21.25 per unit, increasing his beneficial ownership to 11,803.485 units. The Form 4 was signed by proxy (J. Feng) on 08/29/2025. The filing identifies the reporting person as both an officer (President and CEO) and a director and indicates the form was filed by one reporting person.

Positive

• Insider purchase disclosed: 11,803.485 common units acquired
• Transaction details provided: purchase date 08/27/2025 and price $21.25 per unit
• Reporting person role: Jean-Marc Gilson identified as President and CEO and a director
• Form executed by POA: signature by J. Feng dated 08/29/2025

Negative

• None.

Insights

Financial Analyst

Insider purchase of 11,803.485 units by the CEO/director — a straightforward, non-derivative acquisition.

The Form 4 documents a single non-derivative purchase (transaction code P) of 11,803.485 common units at $21.25 each on 08/27/2025, reported for Jean-Marc Gilson. This is a clear disclosure of insider accumulation but the filing does not provide context on total outstanding units or percentage ownership, so the market impact cannot be determined from this form alone.

Corporate Governance Expert

Director and CEO reported a clean, routine open-market purchase reported by proxy.

The filing shows proper Section 16 reporting for an officer/director purchase, signed by POA J. Feng on 08/29/2025. The disclosure follows required Form 4 structure and lists ownership as direct. No amendments or derivatives are reported. The filing contains no indications of related-party transactions or plan-based trades.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Gilson Jean-Marc

(Last) (First) (Middle)

2801 POST OAK BLVD., SUITE 600

(Street)

HOUSTON TX 77056

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Westlake Chemical Partners LP [ WLKP ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

3. Date of Earliest Transaction (Month/Day/Year)
08/27/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Units	08/27/2025		P		95.29	A	$21.25	11,803.485	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

	Jean-Marc Gilson by J. Feng POA	08/29/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What transaction did Jean-Marc Gilson report on the WLKP Form 4?

He reported a non-derivative purchase of 11,803.485 common units on 08/27/2025 at $21.25 per unit.

What roles does the reporting person hold at Westlake Chemical Partners (WLKP)?

The Form 4 lists Jean-Marc Gilson as both President and CEO and a director of WLKP.

When was the Form 4 signed and by whom?

The Form 4 was signed by proxy: Jean-Marc Gilson by J. Feng, POA, dated 08/29/2025.

Does the filing report any derivative or plan-based transactions?

No. The filing shows only a non-derivative purchase (Common Units) and contains no derivative or plan-based transactions.

Was this Form 4 filed by multiple reporting persons?

No. The form indicates it was filed by one reporting person.